JP2729157B2 - Dot impact serial printer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dot impact type serial printer.

[0002]

2. Description of the Related Art A conventional dot impact type serial printer performs printing by pressing an ink ribbon against a printing paper. However, in order to prevent the ink ribbon from contacting the printing paper at a place other than a printing portion and to prevent stains from occurring. For example, actual fairness 1
It has been proposed to provide a ribbon mask between an ink ribbon and a printing sheet in the printing apparatus disclosed in Japanese Patent Application Laid-Open No. 29088 and Japanese Patent Application Laid-Open No. 2-144422.

As shown in the block diagram of FIG. 13, a recent dot impact serial printer includes a printer main control unit 101, a printing mechanism unit 102, and a power supply unit 103.
As shown in the side view of FIG. 14, the printing mechanism unit 102 includes a print head 104, an ink ribbon 105, a platen 106, and a card holder 107. The ink ribbon 105 and the platen 10
6, a structure in which the printing paper 110 is positioned is adopted.

However, FIG. 14 does not show a spacing mechanism for moving the print head 104 and the card holder 107, and a line feed mechanism for moving the printing paper 110.

A card holder 107 for stabilizing the travel of the printing paper 110 between the printing paper 110 and the ink ribbon 105 has a structure in which a ribbon mask 108 is attached to a window 109 as shown in FIG. In this way, the ink ribbon 105 is prevented from directly contacting the printing paper 110 and soiling the printing surface.

[0006] As shown in FIG. 14, the print head 104 includes a dot pin 111 for printing dots, and a dot pin 1.
Armature 112 for driving the electromagnetic coil 11
3, yoke 114, magnet 115, leaf spring 1
16. FIG. 14 shows one dot pin 111, armature 112, electromagnetic coil 113, yoke 114, magnet 115, and leaf spring 116, which are the components of the print head 104, respectively. With current technology, there are generally 24 each).

The dot pin 111 is welded to the armature 112, and the yoke 11 is
The armature 112 sucked by the electromagnetic coil 11
3, a magnetic force opposite to that of the magnet 115 is generated to release the armature 112, and the repulsive force of the leaf spring 116 pushes out the dot pin 111, presses the ink ribbon 105 onto the printing paper 110, and prints a dot. You.

[0008] Since the leading end of the print head 104 is in direct contact with the ink ribbon 105, the ink solidifies,
The fiber scraps of the ribbon adhere, and the diameter of the dot pin becomes apparently thick, and as a result, the printing quality is reduced.

As a method of cleaning the dirt due to the ink at the tip of the print head, a thermal transfer type serial printer disclosed in JP-A-63-154385 and a color serial printer are disclosed. Japanese Unexamined Patent Publication No. Hei 5-171275 for color serial printers and ink jet printers.
No. 147207 has proposed an ink jet printer.

In the thermal transfer type serial printer disclosed in Japanese Patent Application Laid-Open No. 63-154385, an ink ribbon for printing and a felt ribbon tape for cleaning the print head are arranged in two stages in a ribbon cassette, and the print head is manually cleaned. By operating the instruction switch, the ribbon cassette is moved up and down, and the tip of the print head is moved while rubbing the felt ribbon tape to clean the print head.

However, in this mechanism, the ink ribbon and the felt ribbon tape for cleaning are arranged in the upper and lower tiers in the ribbon cassette, so that the ink ribbon cassette becomes large in size and the printer itself becomes large. Naturally, there is a disadvantage that the ink ribbon cassette is also expensive.

Next, the color serial printer suffers from the disadvantage that the color of the ink before the switching remaining in the print head before and after the color switching is mixed with the color of the ink after the switching, so that the printing becomes unclear. Have. In order to prevent the printing from becoming unclear, a print head cleaning mechanism is required.

An ink ribbon of a color serial printer disclosed in Japanese Patent Application Laid-Open No. 2-171275 has a multi-color ink layer having a plurality of color layers and a colorless layer, a head cleaning area provided at the left end, right end, or both ends of a platen. When switching the color of the ribbon, the print head is first moved to the head cleaning area of the platen, and a printing operation is performed using the colorless layer of the ink ribbon to clean the print head.

This mechanism requires a colorless layer of the ink ribbon and a non-printing area on one or both sides of the platen, so that the width of the printer device becomes large and the ink ribbon becomes expensive. Having.

An ink jet printer proposed in Japanese Patent Application Laid-Open No. 5-1707 discloses a method of forming an ink droplet image on an endless transfer belt, and then transferring the ink droplet image onto printing paper. However, the printing method is completely different and cannot be adopted in a dot impact serial printer.

[0016]

SUMMARY OF THE INVENTION In a dot impact type serial printer, a ribbon mask is provided between the ink ribbon and the printing paper in order to prevent the ink ribbon from contacting the printing paper at a place other than the printing location to thereby generate stains. Has been suggested to be effective,
In order to improve the printing quality, the ribbon mask is required to be thin and flexible. Therefore, a polyester film (for example, Mylar film manufactured by DuPont, USA)
However, there is a problem that the life of the ribbon mask is short because the plastic is broken by friction with printing paper or paper jam.

Further, at the tip of the print head, there is a problem that the ink solidifies at the tip of the print head, and fiber scraps of the ribbon adhere to the dot pin, thereby making the diameter of the dot pin seemingly thick, resulting in a decrease in print quality. Therefore, the method proposed for cleaning the tip of the print head has a problem that the size of the printing apparatus is increased and the cost of the consumable ink ribbon is increased.

[0018]

In order to solve the above-mentioned problems, a first invention of a dot impact type serial printer according to the present invention comprises a printer main controller for controlling the operation of the printer, and printing on a printing paper. A dot impact serial printer having a printing mechanism for performing a counter for counting the number of characters to be printed and the number of carriage return / line feed commands, respectively, and a register for storing the lifetime value of the ribbon mask converted into the number of print characters and the number of carriage return / line feed commands, respectively. A comparator for comparing the contents of a counter for counting the number of print characters and the number of return line feed commands and a register for storing the life value of the ribbon mask converted into the number of print characters and the number of return line feed commands. A print amount detection unit, a ribbon cassette retraction / restore control unit that retreats / restores the ribbon cassette from the front end of the print head, and a ribbon cassette A retraction / restore mechanism, a plurality of printing holes formed in a belt-shaped film to form a plurality of continuous ribbon masks, and a ribbon mask winding unit for winding the ribbon mask formed on the belt-shaped film. A print control section and a ribbon mask take-up mechanism section, wherein the print amount detection section detects the life of the ribbon mask, takes up the belt-shaped ribbon mask, and replaces the ribbon mask.

According to a second aspect of the present invention, there is provided a dot impact type serial printer for cleaning a leading end of a print head between a plurality of ribbon masks formed on the belt-like film in the first aspect. The cleaning pad is added to clean the leading end of the print head when the ribbon mask is wound up.

[0020]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing one embodiment of the present invention. In FIG. 1, a dot impact type serial printer according to the present invention includes a printer main control unit 1 for controlling the operation of the printer, and a printing mechanism unit 2 for performing printing on printing paper.
And a print amount detector 3 for counting the number of characters to be printed and the number of return / line feed commands, a ribbon cassette retract / restore controller 4 for controlling the ribbon cassette retract / restore mechanism 5, and a ribbon mask winding mechanism 7. And a ribbon mask take-up control unit 6. However, a power supply unit that supplies power to these components is omitted.

FIG. 2 shows a printer main controller 1 and a printing mechanism 2.
FIG. 3 is a block diagram showing the configuration of FIG. Printer main controller 1
A microprocessor 21 for controlling the operation of the entire printer, a read-only control program storage device 22 storing a control program, an interface line 25
A print information receiving circuit 26 for receiving print character data and a control code (hereinafter, the print character data and the control code are collectively referred to as print information) transmitted through the printer, and a work for temporarily storing the received print information. A storage device 23, a read-only print character font data storage device 24, an uninterruptible storage device 28 backed up by a battery 27 for storing a count value obtained by counting the number of print characters and the number of return line feed commands, A print head driving circuit 29 for driving an electromagnetic coil for supplying power to the dot pins of the print head 30 according to the pattern data, and a carrier lateral feed motor 32 for moving the print head to the left and right with respect to the printing surface of the printing paper are driven. A carrier lateral feed motor drive circuit 31 and a paper feed motor for moving print paper up and down with respect to a print surface. 34, a paper feed motor drive circuit 33 for driving the printer 34, an operation panel 36 for operating the printer and displaying the status of the printer, an operation panel control circuit 35 for controlling the operation panel 36, and a print amount detection unit interface circuit 37. ,
A data bus 38 is included.

The work storage device 23 is divided into a reception information buffer 39 and a print pattern data buffer 40, as shown in the block diagram of FIG.

As shown in the block diagram of FIG. 4, the uninterruptible storage device 28 includes a print character count holding area 58, a return line feed command count holding area 59, and a print character / return line feed command count holding value. It is divided into an area 60.

FIG. 5 is a block diagram showing the configuration of the print amount detection unit 3.

The print amount detector 3 is a decoder 41 for detecting print character data and a return / line feed command from print information.
, Print character number counter 45, return line feed command number counter 4
6, a print character / return line feed command number counter 47, and AND gates 42 and 43 for controlling the count input of these number counters.
, OR gate 44, comparators 48, 49, 50, print character number life value register 51, return line feed command number life value register 52, print character / return line feed command number life value register 53, When the contents exceed the contents of the corresponding lifetime value register, an OR gate 54 for producing a ribbon mask exchange signal generated in one of the comparators 48, 49, 50, a differentiating circuit 55 for detecting the front end of the signal, a monostable multi It comprises a vibrator 56 and a flip prop 57 for producing a signal for temporarily stopping the printing operation. The flip-flop 57 uses a set input on the side marked S, a reset input on the side marked R, and uses a set-side output (signal line 12) as an output (hereinafter, the meaning of S and 8 also for flip-flops 61 and 81). , The polarity of the output is the same as that of the flip-flop 57).

FIG. 6 is a block diagram showing the structure of the ribbon cassette retreat / restore control unit 4, and FIG. 7 is a side view showing the structure of the ribbon cassette retreat / restore mechanism 5, and FIG. FIG. 7B shows a state in which the ribbon cassette is retracted.

The ribbon cassette retraction / restoration control unit 4 includes a flip-flop 61 for generating a coil excitation signal for retracting / recovering the ribbon cassette, and a coil driving circuit 62.
Then, the movement of the ribbon cassette is detected. It is composed of differentiating circuits 63 and 65 for shaping a signal from a detection switch 68 pulled up by a resistor 69, and monostable multivibrators 64 and 66. The differentiating circuit 63 detects a change in the front end of the signal when the detection switch 68 changes from the open state to the closed state, and the differentiating circuit 65 detects a change in the rear end of the signal when the detection switch 68 changes from the closed state to the open state. I do.

The ribbon cassette retracting / restoring mechanism 5 includes a ribbon cassette 71, a ribbon cassette support column 72, a ribbon cassette push-up mechanism 73 including a coil 67 and a plunger 74, and a ribbon cassette push-back mechanism including a spring 76 and a push-back rod 77. 75, and a detection switch 68 for detecting the movement of the ribbon cassette 71.

FIG. 8 is a block diagram showing the structure of the ribbon mask take-up control unit 6, and FIG. 9 is a plan view showing the structure of the ribbon mask take-up mechanism 7.

The ribbon mask take-up control section 6 includes a flip-flop 81 for producing a ribbon mask take-up motor drive signal and a ribbon mask take-up motor drive circuit 82.
And a differentiating circuit 83 for detecting the rear end of the signal of the ribbon mask position sensor 86 for detecting the movement of the ribbon mask, and a monostable multivibrator 84 for shaping the signal. The ribbon mask position sensor 86 checks the position of the ribbon mask using a phototransistor or the like.

The ribbon mask winding mechanism 7 includes a ribbon mask winding motor 85 and a cleaning pad 92.
, A supply spool 93,
Take-up spool 94 and ribbon mask position sensor base 9
And 5.

FIG. 10 is a front view showing the structure of a belt-shaped ribbon mask.

The ribbon mask 91 has a plurality of ribbon mask printing holes 97 through which dot pins pass through a belt-like film, and a plurality of cleaning pads 92 for cleaning the leading end of the print head 30. Thus, one ribbon mask print hole 97 and one cleaning pad 92 correspond to one unit. A ribbon mask position detecting hole 9 is provided at the upper center of the cleaning pad 92.
6, the ribbon mask position sensor 86 detects the ribbon mask position detection holes 96, and controls the movement of the ribbon mask by one unit.

Next, the operation of the embodiment of the present invention will be described.

FIG. 11 is a flowchart for explaining the flow of control.

The microprocessor 21 of the printer main controller 1 sequentially reads out the control program commands from the control program storage device 22 and controls the operation of the printer.

First, as shown in the flow chart 11, a print character number life value register 51, a return line feed command number life value register 5
2. In the print character / return line feed command number life value register 53,
Each life value included in the control program is set via the data bus 38 (S1). (S1) shows step 1 of the flowchart. The same applies hereinafter.

Next, the contents of the print character count storage area 58 in the uninterruptible storage device 28 are transferred to the print character counter 45.
The contents of the return line feed command count holding area 59 are returned to the return line feed command counter 46, and the contents of the print character / return line feed command count holding area 60 are returned to the print character / return line feed command counter 47. (S2).

Next, printing for one line is performed. The printing of one line starts from receiving the printing information of one line (S3). The print information sent through the interface line 25 is received by the print information receiving circuit 26,
It is temporarily stored in the reception information buffer 39 of the working storage device 23. Upon receiving one unit of print information (in the case of a serial printer, generally one line of print information), the microprocessor 21 firstly stores the received print information stored in the receive information buffer 39 of the working storage device 23. From the paper feed motor drive circuit 33 if the print information is a paper feed code or a print head lateral feed code.
Then, the carrier feed motor driving circuit 31 is operated, and the paper feed motor 34 and the carrier feed motor 32 are operated so that the print head 30 is located at the next printing position.

The reception information buffer 3 of the working storage device 23
9 is print character data, the print character data is converted into print pattern data for driving the dot pins by referring to the contents of the print character font data storage device 24 and the print character data is converted to the print pattern data. The data is developed in the buffer 40 (S4).

The contents of the print pattern data buffer 40 are sent to the print head drive circuit 29, and the corresponding dot pin electromagnetic coil of the print head 30 is driven.
Mark the dots on the printing paper. Then, the carrier horizontal feed motor 32 is driven by the carrier horizontal feed motor drive circuit 31 to move the print head by one pitch.

The printing operation is performed by repeating the driving of the dot pins and the driving of the carrier horizontal feed motor 32 (S5).

On the other hand, the print information stored in the reception information buffer 39 is sent to the print amount detection unit 3 through the signal line 11, and the number of print characters and a return / line feed command is counted (S6).

The decoder 41 of the print amount detector 3 receives print information from the signal line 11 through the print amount detector interface circuit 37, and selects print character data and a return / line feed command from the received print information. , Each A
Input to ND gates 42 and 43.

When the microprocessor 21 executes the control program, the counting command signal 10 generated by the microprocessor 21 causes the printing character number counter 45, the return line feed command counter 46, and the OR gate 44 to print character / return line feed command counter 47. Is incremented by the decoding result.

When the printing operation for one line is completed, the comparator 4
Reference numeral 8 compares the contents of the print character number counter 45 with the contents of the print character number life value register 51 holding the life value of the ribbon mask expressed by the number of print characters. , A ribbon mask exchange signal is output to the signal line 13 through the OR gate 54, the differentiation circuit 55, and the monostable multivibrator 56.

Similarly, the comparator 49 compares the contents of the return line feed command number counter 46 with the contents of the return line feed command number lifetime value register 52 holding the ribbon mask life value obtained by converting the return line feed number. When the content of the return line feed command number counter 46 becomes larger than the content of the return line feed command number life value register 52, a ribbon mask exchange signal is output to the signal line 13 through the OR gate 54, the differentiation circuit 55, and the monostable multivibrator 56.

Further, the comparator 50 holds the contents of the print character / return line feed command counter 47 and the print mask / return line feed value obtained by converting the life value of the ribbon mask calculated by adding the print character and the return line feed command number. The contents of the line feed command number life value register 53 are compared with the contents of the print character / return line feed command number counter 47. Circuit 5
5. A ribbon mask exchange signal is output to the signal line 13 through the monostable multivibrator 56 (S7).

When the flip-flop 57 of the print amount detection unit 3 is set by the ribbon mask exchange signal, a print operation temporary stop signal is sent to the printer main control unit 1 through the signal line 12.

Next, the retraction of the ribbon cassette will be described.

When the flip-flop 61 of the ribbon cassette retraction / restoration control unit 4 is set through the signal line 13 by the ribbon mask exchange signal, the coil driving circuit 62
This excites the coil 67 constituting the ribbon cassette lifting mechanism 73.

When the coil 67 is excited, the plunger 74
7B, the front end of the ribbon cassette 71 is pushed up, and the front end of the print head 30 is opened, as shown in FIG.

When the front end of the ribbon cassette 71 is pushed up, the rear end of the ribbon cassette 71 is lowered around the ribbon cassette support column 72, and the detection switch 68 is closed.
Since the voltage V is applied to the detection switch 68 through the resistor 69, the closing of the detection switch 68 is detected by the differentiating circuit 63, and the ribbon mask winding signal is output to the signal line 17 by the monostable multivibrator 64. (S8).

Next, winding of the ribbon mask and cleaning of the print head will be described.

According to FIG. 8, the flip-flop 81 of the ribbon mask take-up control unit 6 controls the flip-flop 81 through the signal line 17.
When set by the ribbon mask take-up signal, the ribbon mask take-up motor drive circuit 82 drives the ribo mask take-up motor 85.

According to FIG. 6, FIG. 8, FIG. 9 and FIG.
When the ribbon mask winding motor 85 is driven, one unit of the belt-shaped ribbon mask 91 (one unit between the ribbon mask position detection hole 96 and the next ribbon mask position detection hole 96) is wound. It is wound around a take-up spool 94. At this time, the cleaning pad 92 slides on the tip of the print head 30, and wipes off the solid matter of the ink and the waste ink ribbon. When the ribbon mask 91 is wound by one unit,
The signal from the ribbon mask position sensor 86 is supplied to the differentiation circuit 8
3, is shaped by the monostable multivibrator 84, resets the flip-flop 81, and at the same time notifies the ribbon cassette retraction / restoration control unit 4 via the signal line 18 as a ribbon mask take-up end signal (S
9).

Next, the restoration of the ribbon cassette will be described.

When the ribbon mask take-up controller 6 is notified of the completion of the ribbon mask take-up via the signal line 18, the flip-flop 61 of the ribbon cassette retract / restore controller 4 is reset, and the ribbon cassette push-up mechanism 73 is reset. The excitation of the coil 67 is stopped.

When the excitation of the coil 67 is stopped, the force of the spring 76 of the ribbon cassette pushing back mechanism 75 causes
The push-back bar 77 is raised, the rear end of the ribbon cassette 71 is pushed up, and the front end of the ribbon cassette is located at the front end of the print head 30. Ribbon cassette 71
Is restored, the contact of the detection switch 68 opens and the signal line 16
Through this, the restoration of the ribbon cassette 71 is notified to the ribbon cassette retraction / restoration control unit 4. The ribbon cassette retraction / restoration control unit 4 detects the trailing end of the signal of the detection switch 68 (indicating that the ribbon cassette has been restored) by the differentiating circuit 65, shapes the signal by the monostable multivibrator 66, and passes the signal through the signal line 14. The completion of restoration of the ribbon cassette is notified to the print amount detection unit 3 (S10).

The flip-flop 57 of the print amount detector 3
Is reset by the ribbon cassette restoration completion signal on the signal line 14, and the temporary stop of the printing operation sent to the printer main controller 1 via the signal line 12 is released.

When the ribbon cassette 71 is restored, the print character number counter 45, the return line feed command number counter 46, the print character / return line feed command number counter 47, the print character count value holding area 58, and the return line feed command number count value are held. Zero is written into the area 59 and the print character / return line feed command count holding area 60 (S11), and the process returns to receiving print information for one line (S3).

On the other hand, a comparison between the contents of the print character number counter 45 and the contents of the print character number life value register 51, a comparison between the contents of the return line feed command number counter 46 and the contents of the return line feed command life value register 52, and a print character / return line feed. Command counter 47
Contents and print characters / return line feed command number life value register 53
In any case, if the content of the counter is smaller than the content of the life value register in any case, the content of the printed character counter 45 is stored in the printed character count holding area 5.
8, the contents of the return line feed command number counter 46 are stored in the return line feed command number count holding area 59, and the contents of the print character / return line feed command number counter 47 are stored in the print character / return line feed command count count area 60. The print data is stored (S12), and the process returns to the reception of print information for one line (S3).

FIG. 12 is a waveform diagram showing the state of each signal line in the above-described ribbon cassette retracting, ribbon mask winding, and ribbon cassette restoring operations.

When the ribbon mask exchange signal from the monostable multivibrator 56 is output to the signal line 13, a print operation pause signal, which is the output of the flip-flop 57, is output to the signal line 12. The printer main controller 1 does not receive print information.

When the flip-flop 61 is set by the ribbon mask exchange signal on the signal line 13, the signal line 1
5, a coil excitation signal is generated, the front end of the ribbon cassette 71 is pushed up, and the rear end of the ribbon cassette 71 is lowered to close the detection switch 68. Since the signal line 16 at the high potential by the pull-up resistor 69 is lowered to the ground potential, this signal change is detected by the differentiating circuit 63, and a ribbon mask winding signal is output to the signal line 17.

When the flip-flop 81 is set by the ribbon mask take-up signal, a ribbon mask take-up motor drive signal is output to the signal line 19, and the ribbon mask starts moving. When the ribbon mask moves, the ribbon mask position detecting hole 96 is moved to the ribbon mask position sensor 8.
6, the potential of the signal line 20 once rises, but when the next ribbon mask position detection hole 96 reaches the ribbon mask position sensor 86, the potential of the signal line 20 decreases again. Since this signal change indicates that one unit of the ribbon mask has been wound, this is detected by the differentiating circuit 83 and output to the signal line 18 as a ribbon mask winding end signal.

The ribbon mask winding motor drive signal on the signal line 19 is cut off by the ribbon mask winding completion signal on the signal line 18, and the movement of the ribbon mask stops. Further, when the coil excitation signal of the signal line 15 is cut off, the ribbon cartridge is restored and the detection switch 68 is opened, so that the signal line 16 returns to the high potential. This signal change is detected by the differentiating circuit 65, and a ribbon cassette restoration end signal is output to the signal line 14.

The counters 45, 46 and 47 and the flip-flop 57 are reset by the ribbon cassette restoration end signal on the signal line 14, and the printing operation pause signal on the signal line 12 is cut off, so that the printer resumes the printing operation. become able to.

[0070]

As described above, according to the present invention, when a ribbon mask of a don't-impact serial printer is formed in a belt shape and the number of characters to be printed and the number of carriage returns reach the life of the ribbon mask, the ribbon cassette is replaced with a print head. By retracting the ribbon mask from the leading end of the ribbon mask and winding the ribbon mask, the ribbon mask can be automatically replaced.

Further, the cleaning pad attached to the belt-shaped ribbon mask automatically cleans the leading end of the print head at the same time as the ribbon mask is automatically replaced, so that a high print quality can be maintained. This has the effect of extending the maintenance cycle of replacing the printhead and cleaning the printhead.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of a dot impact type serial printer according to an embodiment of the present invention.

FIG. 2 is a block diagram of a printer main control unit and a printing mechanism unit according to an embodiment of the present invention.

FIG. 3 is a block diagram showing a configuration of a working storage device in FIG. 2;

FIG. 4 is a block diagram showing a configuration of the uninterruptible storage device of FIG. 2;

FIG. 5 is a block diagram showing a configuration of a print amount detection unit in FIG. 1;

FIG. 6 is a block diagram showing a configuration of a ribbon cassette retract / restore control unit of FIG. 1;

FIG. 7 is a side view showing the configuration of the ribbon cassette retreat / restore control unit in FIG. 1;

FIG. 8 is a block diagram showing a configuration of a ribbon mask take-up control unit in FIG. 1;

FIG. 9 is a plan view showing the structure of a ribbon mask take-up mechanism of FIG. 1;

FIG. 10 is a front view showing the structure of a belt-shaped ribbon mask.

FIG. 11 is a flowchart for explaining a control flow;

FIG. 12 is a waveform chart showing a state of each signal line.

FIG. 13 is a block diagram showing an example of a dot impact type serial printer according to the related art.

FIG. 14 is a side view showing an example of a printing mechanism of a dot impact type serial printer according to the related art.

FIG. 15 is a front view showing an example of a card holder of a dot impact type serial printer according to the related art.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Printer main control part 2 Printing mechanism part 3 Print amount detection part 4 Ribbon cassette retraction and restoration control part 5 Ribbon cassette retraction and restoration mechanism part 6 Ribbon mask winding control part 7 Ribbon mask winding mechanism part

Claims (2)

(57) [Claims] 1. A dot impact serial printer having a printer main controller for controlling the operation of a printer and a printing mechanism for printing on printing paper, a counter for counting the number of characters to be printed and the number of carriage return / line feed commands, respectively. , A register that stores the lifetime value of the ribbon mask converted to the number of print characters and the number of return line feed commands, the contents of a counter that counts the number of print characters and the number of return line feed commands, and the number of print characters and the number of return line feed commands. A print amount detection unit composed of a comparator for comparing the contents of the registers storing the life values of the ribbon masks, a ribbon cassette retraction and restoration control unit for retracting and restoring the ribbon cassette from the end of the print head, and a ribbon cassette retraction.・ Recovery mechanism and a belt-shaped film provided with multiple printing holes to form a continuous multiple ribbon mask A ribbon mask take-up control section and a ribbon mask take-up mechanism section for taking up a ribbon mask formed on the belt-shaped film. The print amount detection section detects the life of the ribbon mask, A dot impact type serial printer characterized by winding a ribbon mask and replacing the ribbon mask. 2. A cleaning pad for cleaning a leading end of a print head is added between a plurality of ribbon masks formed on the belt-shaped film, and a leading end of the print head is cleaned when the ribbon mask is wound up. The dot impact type serial printer according to claim 1.